[satta535i]

On my n55 ps2 ewg ive replaced my hpfp x2 lpfp x2 got a bpm4 changed o2 sensors cleaned all tmap sensors yet my fuel pressure keeps crashing and cutting and i am only running 14lbs of boost any suggestions?

[thejeremyman9]

Post a log.

Did you check LPFP install? Happens even with a full tank of gas? A little more history of when/why you did each of the HPFP and LPFP installs might help.

[satta535i]

Originally Posted by thejeremyman9

Post a log.

Did you check LPFP install? Happens even with a full tank of gas? A little more history of when/why you did each of the HPFP and LPFP installs might help.

https://www.bootmod3.net/log?id=5fe1...729b7aac9ab973

https://www.bootmod3.net/log?id=5fe1...0c60d752216a2a

at first i thought it was the hpfp so i replaced it then my tuner said check the o2 sensors replaced them and said to replace the lpfp i replaced it with another walbro 450 a couple weeks go by still cant figure it out and the car start to cut more and more thought maybe my hpfp was faulty and replaced it and it made no difference but now i have a studder around 3k rpm so i cleaned all the sensors and cary jordon tried his best to support my fuel system thru a tune and this is where we are at this log is before i replaced the hpfp again as now i really cant floor it it just cuts out i also have changed the spark plugs 2x and got new coils its been 3k miles with the ps2 and never got any codes at all for this issue at all

[satta535i]

Originally Posted by satta535i

https://www.bootmod3.net/log?id=5fe1...729b7aac9ab973

https://www.bootmod3.net/log?id=5fe1...0c60d752216a2a

at first i thought it was the hpfp so i replaced it then my tuner said check the o2 sensors replaced them and said to replace the lpfp i replaced it with another walbro 450 a couple weeks go by still cant figure it out and the car start to cut more and more thought maybe my hpfp was faulty and replaced it and it made no difference but now i have a studder around 3k rpm so i cleaned all the sensors and cary jordon tried his best to support my fuel system thru a tune and this is where we are at this log is before i replaced the hpfp again as now i really cant floor it it just cuts out i also have changed the spark plugs 2x and got new coils its been 3k miles with the ps2 and never got any codes at all for this issue at all

happens with a full tank of gas well and i have rechecked the lpfp a bunch if times

[thejeremyman9]

Only one of the logs worked so i looked at that one. It seems strange that you have the sudden drops and quick recovery when MAF/boost don't change over those timescales. My best guess would be its the FPR (or whatever you want to call it that is controlling the HPFP pressure); maybe its "leaking"/not holding fuel flow back as it should so you cant maintain pressure even if you have more than enough pump. It's the next piece of the fuel system if you have confirming everything else upstream.

I also noticed that your AFR readings and STFTs are prety erratic in some places. Like you are jumping from 14s to 10s AFR over a single timestep in the log which does not seem normal. This also causes fuel trims to spike in some cases. This happens a lot more often than your HPFP dips though.

[n55david]

who's walbro kit did you use?